Societies and cultures depend on shared knowledge – for instance about different social roles and positions, the norms and behaviour associated with these roles, rights and duties, shared values or a common cultural heritage to name but a few examples. In order to be shared, knowledge on the one hand needs to circulate within a specific group. And on the other hand, of course, knowledge (or bits and pieces thereof) is also constantly exchanged with other such groups – purposefully or not. Hence, knowledge – willingly or not – is constantly on the move.